Work feeding mechanism



May 29, 1934. R. L. HARTWELL WORK FEEDING MECHANISM Filed Jan. 23, 1933 INVENTOR EAL/ H LH/mrwm 4%), V W

ATTORNEYS.

Patented May 29, 1934 1,960,537

UNITED STATES PATENT OFFICE 1,960,537 WORK FEEDING MECHANISM Ralph L. Hartwell, Agawam, Mass. Application January 23, 1933, Serial No. 653,073 4 Claims. (01. 164--117) This invention relates to improvements in shoe and is adapted to rest on and be bolted mechanism for feeding stock, usually in wire or to the bolster or bed of the punch press. Usustrip form, to the cooperating members of a ma ally, although not necessarily, there are guide chine, such for example as a punch press, by pins, such as d, fixed in and upstanding from 5 which members the stock is worked in any dethe stationary element 1), which are slidably 6.0

sired way, as by cutting, piercing, shaping and received in the movable member a. Thesememthe like, bers a and b may carry any desired kind of tools The invention has for one object the'provision for working the metal or other kind of strip fed of a work gripping device for use either in feedtherebetween. As shown, there are punches e l0 ing the work to the aforesaid cooperating memwhich are carried by the member a and co- 65 bers or for holding the work against the return operate with a die I carried by the member I) travel of a work feeding device, or for both. to perforate the work; and a forming punch g More particularly, the invention provides a carried by the member a, which cooperates with work gripping device which is of relatively sima pressure pad h, and the adjacent walls ion ple and inexpensive construction and at the same which it slides, to shape the work. The form- 7 0 time positive and efficient in action. ing punch also has a shear edge; ;i, which oper- The invention also has for an object to proates to sever the forward end of; the stock coinvide in a work feeding mechanism a pair of cidentally with the shaping of the same by the such work grippers, mounted in laterally spaced elements g, h and i. A portion of the usual 20, relation with respect to the direction of the feedoperating rod for the pressure pad is shown at ic, 75. ing movement and each mounted on a support, such rod controlling the vertical movements of the adjacent faces of the two supports presentthe pad h with respect to the walls 2'. The'die 1 ing faces paralleling the work to be fed and has the usual stripper plate I, which holds the functioning as side guides therefor. stock from rising during the retraction of the Other objects of the invention will appear as punches e following the perforation of the stock 80.- the detailed description proceeds and will be thereby. Openings mare provided in the die 7 pointed out in the appended claims. i and bolster b to allow the slugs or pieces of The invention will be disclosed for illustrative metal punched out by punches e to pass downpurposes in connection with the accompanying wardly therethrough.

drawing, in which: A In this particular case the stock is a strip n 85.

Figs. 1 and 2 are top plan and front elevational of metal. In the first instance this strip is adviews, respectively, of a work feeding mechanism vanced first beneath the punches e which perembodying my invention; V V forate the stock on the down stroke of the ram Fig. 3 is a cross sectional view thereof taken of the press. On the next upstroke ofthe ram,

on the line 33 of Fig. 2; and I H the strip will be advanced by another measured 9.0

Figs. 4 and 5 are front and side elevational length and the part perforated by punches c will views, respectively, of one of the work grippers. be carried into position to be shaped and severed In the drawing, my invention has been disby the elements g,-h., i and 7' on thenext downclosed in connection with a work feeding device, stroke of the ram. At the same time the punches 40 such as may be used to feed the work to the e will perforate a section of the strip n which cooperating and relatively movable members, lies just to the left of the severed section. such as dies, of a punch press. It will be ap- The feedingmechanism includes a reciprocable preciated that the work grippers may be used member 10, operable on one stroke to gripthe for many other purposes and the one use herein strip n and advance it a measured distance and 5 disclosed is merely illustrative of one of the many operable on the other stroke to move without uses of which the invention is capable. causing movement of the strip n. This member Referring to Figs. 1 and 2, the die'set, chosen 10 is mounted on a carriage 11 which is slidably by way of illustrative example as a setting or mounted on ways 12, formed on a bracket1 3, background for the invention, willbe described. fixed to the bed I) in any suitable way, as by the 50 The cooperating and relatively movable members capscrews'ii. The feeding means also includes a and b are adapted for connection to the coa suitable actuating means for effecting reciprooperating and relatively movable parts of a cation of the carriage 11 and in this case a cam punch press. The member a is a punch holder 15 serves the. purpose-such cam being suitand is provided with a shank c to fit the ram 1' ably fixed as by the cap screws 16 to the mem- 55 of the punch press. The member I) isthe die her a. This cam serves by coaction with a roll 1'7, mounted on the carriage 11, as best shown in Fig. 3, to positively move the carriage to the left as viewed in Fig. 2. Such movement of the carriage also serves to stress a spring 18 which, when permitted by the cam, serves to move the carriage to the right and effect the advance stroke of the feeding member 10. The spring 18 is coiled around a rod 19, which at one end is fixed as by the screw threads indicated, to an car 20 on carriage 12. Rod 19, at its other end, is slidable in an ear 21 formed on the left hand end of the bracket 13. The last named end of rod 19 is threaded to receive a nut 22 and lock nut 23. These nuts are adjustable on red 19 and the position of nut 22 on the rod controls the amount of the feeding movement of the carriage 11. As will be obvious, when cam 15 rises, the spring 18 will advance the carriage 11 until nut 22 abuts the ear 21. The cam 15 always moves the carriage back to a predetermined position, being that shown in Fig. 1 wherein a vertical dwell surface 15 of the cam engages roll 17 and allows the member a to descend and cause an operation .to be performed on the strip n without moving 5 the carriage. With the parts positioned as shown in Fig. 2, the feeding mechanism may be set in a very simple way by simply moving nut 22 on rod 19 until its right hand face is spaced from the left hand face of ear 21 by a distance equal to the amount of feed desired. The nut 22 is then locked in this position by turning up the lock nut 23. Thus, the feeding mechanism is not only simple in construction but more important still, it is very simple and convenient to adjust. Moreover, it is easily adjusted with close accuracy and can be set to produce feeds from a minimum of 1/ 64 of an inch up to a maximum determined by the length of the cam, by increments as small as one one thousandth of an inch if desired.

It will be seen from Fig. 2 that the cam 15 descends below the plane of the top of the bracket 13 and this bracket is cut away as indicated at 24 in Figs. 1 and 2, to provide the necessary clearance and permit the cam to descend the distance necessary for the tools 6, g and y" to perform their work on strip 11.

The feeding gripper 10 is mounted in a bracket comprising a horizontal base 25, a vertical wall 26 upturned therefrom, a vertically disposed lug 27 integral with and turned at right angles to the wall 26 and a horizontally disposed ear 23, integral with the lug 2'7 and bent forwardly from its upper edge to lie at right angles thereto. The

, vertical wall 26 lies contiguous with a vertically upstanding web 29, forming part of the support for the described roll 17, as will be clear from Fig. 3. Wall 26 is secured by cap screws 30 or in any other suitable way to this web 29. This wall 26 also forms a guide for one edge of the strip n, as will be clear from Fig. 3. The strip n rides over the upper face of the base wall 25 and, to prevent the forward end of the strip from catching on the left hand edge of the base wall 25 when the strip is fed into the machine, such edge is bevelled as shown in Fig. 4. A cap screw 31 is threaded into the lug 2'7 and locked thereto by a nut 32, such screw being disposed horizontally in overlying relation with the base wall 25 and with its head 33 spaced a substantial distance from the lug. The gripper 10 has a vertically disposed slot 34 therein, through which slot the body of screw 31 passes. At the upper end of this slot there are two laterally spaced lugs 35 formed on the gripper 10. The upper edge of the grip per is engaged by the lower end of a screw 36 threaded into the ear 28 and held in adjusted position by a lock nut 37. A conically formed coil spring 38 encompasses screw 31 with its end of small diameter abutting the head 33 of the screw and its end of large diameter abutting the adjacent face of the gripper 10. The free end of the spring is engaged between the lugs, as best shown in Fig. 5, for the purpose of holding the spring from turning with the screw 31 whenever the latter is turned. The largest end convolution of spring 38 presses upwardly against the lugs 35 and tends to hold the upper edge of the gripper engaged with the screw 36. The gripper is adjusted to lie in downwardly diverging relation with respect to the vertical wall 27, with its lower edge lying against the strip 11 and its upper edge engaged with the abutment screw 36 and the upper portion of its back face pressed against the vertical wall 27. It will be clear that when the gripper bracket is moved to the right as viewed in Fig. 4, the gripper 10 will tend to dig into the strip n and cause the latter to be moved forwardly with the bracket and the carriage 12 to which it is secured. Also, that when the bracket is moved to the left, the gripper will ride freely over the top of strip n without moving the same.

For convenience in manipulating the gripper by hand, as for example to release it and allow the strip to be fed forward by hand, a finger piece 40 is provided on one of the upper corners of the gripper. The screw 36 is adjustable to allow the gripper to be properly set to engage strips of various thicknesses.

For preventing retrograde movement of the strip n a holding device 41 of exactly the same construction as the gripper 10 is provided. The device 41 is mounted in the same way as described, as will be clear from Fig. 2 but the supporting bracket is somewhat diiferently formed. The vertical wall 42 corresponds to the wall 2'7 above described, and this wall 42 is integral with a right angularly disposed wall 43, which in turn is secured to a base wall 44, having a slotted extension 45, secured to the left hand end of bracket 13 by a bolt 46 at a location out of the path of the carriage 12. The strip 11 rides over and rests upon the base 44 and the gripper 41 cooperates with the strip n and base 44 in the same way as above described in connection with the gripper 10. The vertical wall 43 forms a guide for one edge of the strip n. Thus, as shown in Fig. 1, the strip is guided between the two laterally spaced vertical walls 26 and 43. the strip n to be fed forward beneath it by the gripper 10 but will dig into the strip and hold it from movement in a reverse direction. The slot in the extension 45 permits the gripper 41 and its associated guide 43 to be adjusted for strips of various widths.

The operation of the feeding mechanism will now be described. The grippers 10 and 41 are first adjusted for the thickness of strip to be used and the position of the guide wall 43 is properly located so as to cooperate properly with the wall 26 in guiding the strip to the work forming tools. Then, with the parts positioned as in Fig. 2, the nuts 22 and 23 are adjusted on rod 19 to secure the desired length of feed. With these initial adjustments made, they need not thereafter be altered because the feeding mechanism is incorporated into the die set and always remains therewith, being removable with the die setfrom the punch press or other machine. Assuming The gripper 41 allows.

that the parts are now positioned as in Fig. 2 and that the strip 12 overlies the various forming tools in the proper relation as indicated, then when the member a descends further the punches e will perforate one section of strip n and the members 9, h and i will bend into form another and previously perforated section of the strip and the last named section will be severed from the first named section by the shear edge 7'. Then as the member it rises, the roll 17 will eventually ride off the dwell surface 15 and onto the surface 15 of the cam, thereby releasing the carriage and allowing it to be moved forward under the force of the previously stressed spring 18. As the carriage moves to the right, the strip n will be advanced by another measured length by the gripper 10, thus bring ng the previously perforated section of the strip n into position to be shaped by the tools 9, h and i, and another section into proper relation with the die 1 to be operated on by the punches e. As the member a descends, the cam 15 acting on roll 17, will force the carriage to the left and again stress the driving spring 18, forcing the carriage back, during which action the gripper 10 rides freely over the upper face of the strip and the strip is held against return movement by the gripper 41.

The invention has been disclosed herein, in an embodiment at present preferred for illustrative purposes, but the scope of the invention is defined by the appended claims rather than by the foregoing description.

What I claim is:

1. In work feeding mechanism, a work gripping device including a member on which a portion of the material to be fed is adapted to rest and a wall connected to and upstanding from said member and disposed normal to the direction of the feeding movement, a projection from said wall overlying said member in substantially parallel relation and carrying an abutment, a work gripping plate mounted in inclined relation with said wall with one edge engaged with said abutment and wall and the opposite edge adapted to engage the material to be fed, and resilient means tending to hold said plate thus positioned.

2. In work feeding mechanism, a work gripping device including a member on which a portion of the material to be fed is adapted to rest and a wall connected to and upstanding from said member and disposed normal to the direction of the feeding movement, a projection from said wall overlying said member in substantially parallel relation and carrying an abutment, a work gripping plate mounted in inclined relation with said wall with one edge engaged with said abutment and wall and the opposite edge adapted to engage the material to be fed, a stud fixed to said wall and passing through said plate, and a conical spring encircling said stud and pressing said plate and tending to force the first named edge thereof against said wall and tending also to lift the plate and force the first named'edge thereof against said abutment.

3. In a work feeding mechanism, a work gripping device including a member on which a portion of the material to be fed is adapted to rest and a wall connected to and upstanding from said member and disposed normal to the direction of the feeding movement, a projection from said wall overlying said member in substantially parallel relation and carrying an abutment, a work gripping plate mounted in inclined relation with said wall with one edge engaged with said abutment and wall and the opposite edge adapted to engage the material to be fed, and resilient means acting on said plate and tending to force it toward said wall and also to lift it whereby the first named edge of the plate will be held against said wall and against said abutment.

4. In work feeding mechanism, a work gripping device including a member on which a portion of the material to be fed is adapted to rest and a wall connected to and upstanding from said member and disposed normal to the direction of the feeding movement, a projection from said wall overlying said member in substantially parallel relation and carrying an abutment, a work gripping plate mounted in inclined relation with said wall with one edge engaged with said abutment and wall and the opposite edge adapted to engage the material to be fed, resilient means tending to hold said plate thus positioned, and a finger piece bent forwardly from said plate near one upper corner thereof for manually moving it against the force of said resilient means to disengage it from said material.

RALPH L. HARTWELL. 

